imsa – Brembo Performance and Brembo Racing

Brembo Carbon Materials (CCM, CCM-R, and racing carbon)

Brembo Offers 3 Types of Carbon Based Discs:

Carbon Ceramic (CCM): street use
Carbon Ceramic (CCM-R): street and track use
Carbon-Carbon: race use

Original Equipment Carbon Ceramic Material (CCM):

CCM discs supplied for the OEM are designed to offer significant weight savings over typical cast iron OEM discs while offering outstanding performance and very long life under typical street use. However, OEM CCM discs have limitations for serious performance driving and dedicated track use.

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Carbon ceramic offers significant weight savings over typical cast iron OEM discs

OEM CCM discs do not wear in the same way as cast iron discs. The life on CCM discs is determined by the loss of disc mass as the material oxidizes. This cannot be verified by simply measuring the overall disc thickness like traditional iron discs. Each disc assembly is weighed after assembly and then the minimum allowable weight is permanently etched into the bell. In order to check the weight after use, a cleaning procedure must be performed before checking the weight.

An exhaustive on-road and on-track test program is needed during vehicle development in order to manage airflow to the discs in order to provide enough cooling to achieve satisfactory component life. Oxidation increases rapidly with temperature and it is for this reason that extended high temperature use such as experienced on the race track dramatically reduces the discs life.

OEM carbon ceramic (CCM)

OEM CCM discs are designed to be used with very specific brake pad materials. While there are other pad materials supplied on the market by various pad manufacturers claiming to be “CCM friendly”, there is currently no established validation process for such materials. Pad materials developed for cast iron brake discs will have considerably different results when used on CCM if the various factors are not considered. Pads used with CCM discs also have much greater surface area than would be present in a similar performing cast-iron system which somewhat offsets the weight savings of the disc.

Production Process Time: Relatively quick production time (for a carbon-based material), approximately 4 weeks (1 month).

Brembo Racing IndyCar carbon racing discs & pads

Brembo Racing Carbon-Carbon:

Brembo carbon-carbon materials are used in the top levels of professional motorsports in such racing categories as open wheel (i.e. Formula 1 and IndyCar) and sportscar racing (i.e. LeMans and LMP1) amongst others. The latest motorsport carbon-carbon discs offer stable performance over a wide temperature range, are extremely lightweight, and are highly wear resistant.

Brembo F1 carbon-carbon disc

While many companies market high performance and racing carbon materials, there are only a few manufacturers who sell carbon-carbon brake materials to the top levels of professional motorsports. These are: Brembo, Carbone Industrie, and Hitco (a subsidiary of the Brembo SGL Group). Brembo supplied over 60% of the Formula 1 field in 2014 and is the sole supplier for IndyCar, Along with supplying brake systems to both factory run Porsche and Audi LMP1 efforts in the FIA WEC (World Endurance Championship) for 2015. It is quite normal for an LMP1 car racing at the 24 hours of LeMans to finish the endurance race without any disc or pad change.

Side profile of a carbon-carbon disc.

Racing carbon-carbon systems differ from other brake systems in that they utilize a pad that is also made of carbon-carbon material very similar to the disc material. There are specific carbon-carbon formulations for the disc and pads that can be chosen to suit the system to the needs of the racing series, car, track, or driver.

Wear occurs in a carbon-carbon system both through material thickness reduction, as well as by oxidation. During a braking event, the temperatures reached in a carbon-carbon system can be well in excess of those seen in a racing cast-iron system, but the airflow management must be such that the temperatures are brought down significantly to avoid excessive oxidation. Racing carbon-carbon systems do not work well at low temperatures, and are for motorsports use only.

Production Process Time: Approximately 28 weeks (7 months) for production from start to finish.

Brembo CCM-R discs.

Brembo CCM-R:

Brembo created the CCM-R material by applying the knowledge gained through developing and supplying carbon-based brake materials for both OEM road use and racing applications. Brembo CCM-R discs are sized and cross-drilled similar to the OEM CCM material discs, however, the base material, production process and construction is more in-line with Brembo carbon-carbon racing discs. CCM-R discs were developed with high-performance and racing use in mind.

Debut of CCM-R for the Nissan GT-R (R35)

Brembo CCM-R material comparisons to CCM:

Increased material strength, thermal conductivity, and coefficient of friction
Reduced temperatures
Significant increase in disc life, especially under track conditions
Density similar to CCM, but potential for reduced weight due to ability to reduce disc and pad dimensions
Wear extent can be determined by visual inspection

CCM-R discs and pads are delivered pre-bedded with a specific friction material for street and track use which will operate in a wide temperature range. If the customer is using the vehicle for primarily track or race use, a race-only material can be specified.

Production Process Time: Approximately 28 weeks (7 months) for production from start to finish.

Porsche 997 GT3R Hybrid Equipped with Brembo Racing brakes – ALMS 6 hour endurance race.

Porsche 997 GT3R Hybrid Equipped with Brembo Racing brakes – ALMS 6 hour endurance race

Pre-Bedding:

Pre-bedding is the process of transferring pad material to the disc surface in a controlled environment. It is critical to have a transfer layer of pad material on the CCM-R disc to generate friction. Due to the material strength of CCM-R and the high level of surface hardness, it takes considerable pressure and temperature to transfer pad material onto the disc surface. This is done on a high inertia brake dynamometer using very specific computer controlled programs at the Brembo factory.

Carbon ceramic pads that were used to pre-bed the discs

Brembo CCM-R discs pre-bedded and matched to specific friction materials.

Representative Component Weights:

Brembo 355x32mm, 53mm annulus Cast-Iron 72-vane disc ring: 16.5 lbs
Brembo 360x32mm, 64mm annulus CCM-R disc ring: 7.5 lbs
Brembo 355x32mm, 53mm annulus Carbon-Carbon disc ring: 5.8 lbs

Typical Pad Weights – For Perspective:

Brembo 6-piston 26mm thick Cast-Iron disc race pad: 1.8 lbs
Brembo 6-piston 17mm thick CCM-R disc pad: 2.7 lbs
Brembo 6-piston 26mm thick Carbon-Carbon race pad: 0.7 lbs

Brembo CCM-R Grain Structure and Brembo Carbon Carbon grain structure

The Long Beach Grand Prix takes place every year on the famed Long Beach Street Circuit. The IMSA United Sportscar Championship race and Pirelli World Challenge series both host challenging sprint races at the Long Beach Grand Prix. Brembo Racing is a technical partner and supplier to the top teams competing in both series. Racing on street circuits pose several challenges to the teams as well as setting up a reliable brake package for the driver.

Street Circuits are challenging for teams for the following reasons:

– Limited track time for the drivers and teams to dial in car setup, hard on equipment (brakes, tires, dampers, etc…).
– Limitations in circuit grip levels due to dirt as well as pavement changes/bumps/curbs. The circuit’s grip level always changes thru the race weekend as different series run on the track adding different types of rubber directly on the racing line. This can affect car balance and brake performance overall.
– Passing opportunities are few as any type of contact means instantly being taken out of the race. It’s quite difficult for drivers take huge risks (and what risk are taken have to be precise & calculated) as there are concrete barriers which line the course and contact with these barriers can immediately take you out contention for the race win.

Having consistent, reliable brakes which offer the driver maximum control and modulation can give drivers a significant advantage in Turns 2, 9 and 11 where all the passing opportunities are under braking.

Street Circuits are demanding on the brake systems for the following reasons:

– Long High speed, high pressure brake zones which are generally “point and shoot”. Typical GT Cars hit 150-160 miles per hour in the main straight on Shoreline drive, braking down to 50 mph roughly. Driver confidence in the initial “attack” and brake “feel” without over-slowing the cars is important here.
– Bumpy road surface which is can make a driver brake early and spend more time on the brake pedal trailing off. (on motorsport ABS equipped GT cars, active use of the ABS can raise disc temperatures even more).
– Concrete barriers always limit effective airflow to the brakes causing the average disc temperature to be high (About 550-650 C on a Typical GT application).
– In categories where brake setup is “free or open to change”, teams always have to choose between having a higher thermal capacity setup versus running the lightest brakes as possible to help the driver have the competitive on-track advantage. The optimum balance of braking durability, reliability and performance is key.

Depending on the team’s desired direction, the team can choose the specific brake disc and friction options to suit their needs.

In the IMSA United Sportscar Race: Wayne Taylor Racing’s Daytona Prototype took overall honors equipped with Brembo Racing carbon-carbon brakes. In the GTLM class, the Risi Competizione Ferrari 458 GTLM finished a very competitive 2nd equipped with Brembo Racing brakes.

In the Pirelli World Challenge race: All the podium finishing cars were equipped with Brembo Racing brakes (Winner – R.Ferri 458 GT3, Runner Up – Dyson Racing Bentley GT3, and third place – Effort Racing Porsche 997 GT3R)

Photos: NH512 Photo, Nicolas Hur